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191.
Serum leptin levels during the periparturient period in cows   总被引:1,自引:0,他引:1  
Serum leptin concentrations were measured in antenatal and postnatal cows housed at two different locations. The mean serum leptin concentration was 9.2 +/- 0.6 ng/m l (n=22) in one group, and was slightly lower in the other (7.4 +/- 0.4 ng/ml, n=54), probably because of the different nutritional conditions between the two groups. There was no consistent variation in relation to the menstrual cycle and the periparturient period in both groups. Moreover, serum leptin concentrations during the periparturient period were independent of the number of delivery and the incidence of mastitis and milk fever. These results are quite different from those in rodents and human, suggesting the different regulatory mechanism of circulating leptin concentration in cows.  相似文献   
192.
In this study, we evaluated whether five rapid antigen detection kits for human influenza could be used for the diagnosis of equine influenza (EI). Limiting dilution analyses showed that Directigen Flu A+B and ESPLINE INFLUENZA A&B-N had the highest sensitivities to equine-2 influenza viruses (EIVs) among the kits investigated. From the results of virus detection in nasal swabs taken from horses infected with EIV, these two kits could produce positive results in reasonable agreement with those obtained by virus isolation or RT-PCR, suggesting that these kits could be useful for rapid diagnosis of EI in the field. However, from the viewpoint of specificity for EIV, Espline seems to be superior to Directigen.  相似文献   
193.
Two trials were conducted to evaluate the therapeutic and prophylactic activity of milbemycin oxime (Interceptor, Novartis Animal Health) against the eye-worm Thelazia callipaeda (Spirurida, Thelaziidae) infection. In Trial 1, the therapeutic efficacy of milbemycin oxime was evaluated in 55 naturally infected dogs treated with min. 0.5mg/kg milbemycin oxime. The dogs were clinically examined for the presence of eyeworms before and again 7 days after treatment. Dogs still positive were given a second treatment and re-checked again a week later. Forty-eight of the 55 dogs tested negative 1 week after treatment (87.3% reduction of infection rate). Following the second treatment 6 of these 7 dogs tested negative 1 week later resulting, after two treatments, in a reduction of infection rate of 98.2%. In Trial 2, the prophylactic efficacy of milbemycin oxime was evaluated in 60 uninfected dogs. Thirty dogs were treated with milbemycin oxime monthly from June to November with the recommended dose rate for the prevention of heartworm disease (> or =0.5mg/kg), 30 dogs served as untreated controls. At the end of the trail 1 dog in the treated group and 10 dogs in the control group became infected during the trial. The incidence of infection differed significantly between treated and control dogs (p=0.0056). The efficacy of the prophylactic use of a monthly treatment with milbemycin oxime showed 90% efficacy in reducing T. callipaeda infection rate.  相似文献   
194.
Inductively coupled plasma mass spectrometry (ICP-MS) analysis was used to determine iodine and bromine concentrations in several Austrian agricultural soils. The determined iodine concentrations in topsoils vary between 1.1 and 5.6 mg kg—1, the arithmetic mean amounted to 3.1 mg kg—1, bromine contents are always higher than the corresponding iodine values, varying between 2.4 and 11.9 mg kg—1 with an arithmetic mean of 5.7 mg kg—1. Due to their different geological origin lime-free soils on average contained significantly less iodine and bromine than calcareous soils. In general the observed values are supported by literature values from other countries far from the sea. A correlation analysis of results with several soil parameters resulted in positive correlations with clay content and a negative relation to sand content. In the group of calcareous soils I and Br correlated positively with organic carbon contents and exchangeable calcium.  相似文献   
195.
196.
The histological reaction of current shoots of the Japanese cedar,Cryptomeria japonica, inoculated withCercospora sequoiae was investigated. Wound periderm was formed on current shoots of the cedar on and after the 4th day after inoculation. In the cells of the cork layer, lignin and suberin were deposited, and a phenolic substance was accumulated. In other inoculated samples, plasmolysis, contraction of the cells and necrosis of the tissues were also observed. On the 32nd day, wound perioderm and phellogen were observed in samples of the tissue inside the necrotic tissues in response to hyphal invasion. Occurrence of wound periderm and phellogen in tissues of the needles was confirmed in the inoculated samples although no hyphae were observed in and around the tissues. These results suggest that this fungus causes necrosis of host tissues and induces defense responses. A part of this paper was presented at the 106th Annual Meeting of the Japanese Forestry Society (1995).  相似文献   
197.
Although it is well known that sap exudation during early spring in temperate deciduous trees occurs in response to daytime warming and nighttime cooling, the mechanisms of the process are not yet fully understood. Previous theories suggested that changes in stress in the wood caused by daytime heating and nighttime cooling might be linked with sap flow. Consequently, a study of itaya-kaede maple (Aver mono) and shirakamba birch (Betula platyphylla var.japonica) looked at tangential strains. One-hour intervals for 3 years of the tangential strains on the inner bark of stem and root were measured in itaya-kaede maple and shirakamba birch during the sap exudation season. The measurements indicated different mechanisms of sap exudation in these two trees. During the sap exudation season in late March, when the temperature fluctuated around 0°C, the tangential strain in the root of itaya-kaede maple showed expansion in the daytime and contraction at night. Conversely, in early April the tangential strain in the root of shirakamba birch exhibited contraction in the daytime and expansion at night. The changes in tangential strains in itaya-kaede maple were attributed to conditioning, a known concept used to explain the uptake mechanism of soil water in maple and its exudation during early spring. However, because the change in tangential strain in the roots of shirakamba birch was similar to that found during the rampant season, sap exudation was not attributed to conditioning but to the plentiful supply of water from the roots. The implications of these mechanisms are that different sap harvesting techniques may be appropriate for different tree species.  相似文献   
198.
A new method for predicting understory light levels around an artificial canopy gap prior to the selective cutting is presented. In two even-aged coppice stands, hemispherical photographs were taken at a height of 1.3 m, and crowns of each canopy stem on the photographs were identified by field observations. To predict light levels after cutting, we used computerized images of the hemispherical photographs, in which we digitally erased all crowns to be cut (named ‘erasing method’). Light levels were calculated by an analyzing program; HEMIPHOT. Light levels predicted by the ‘erasing method’ were compared with that calculated by the ordinary photograph-analyzing method using photographs taken after the actual cutting. The correlations between the two methods were highly significant in the two stands. The ‘erasing method’ is eminently effective for the prediction of understory light levels in an artificial canopy gap.  相似文献   
199.
One of the roles of growth stress in branch shape formation was investigated using a weeping-type Japanese cherry,Prunus spachiana. Negative released strains, caused by longitudinal tensile growth stresses, were detected in the upper side of gibberellin A3-treated (GA3-treated) and control branches. The mean value of the released strain in the upper side of the treated branches was –0.104%, which was larger than the value (–0.067%) observed in the control branches. Both branches formed tension wood in the upper side of the xylem, and the treated branches formed tension wood near the pith as well. This suggested that the treated branches generated larger tensile growth stress from the early growth stages. The successive generation of growth stress from the early growth stages was considered to generate forces large enough to bend the branch upward.  相似文献   
200.
Cooked spaghetti of various types (fresh, dried, frozen, luncheon, and long‐life spaghetti) was examined for moisture distribution by magnetic resonance imaging (MRI). Moisture content was calculated from spinspin relaxation time (T2) of water proton, based on the correlation between T2 and moisture content of pulverized durum semolina standard gel samples. Boiled samples of dried and frozen spaghetti had a distinct low moisture region at the center, which was not clearly observed in the other types of boiled spaghetti samples. In particular, the moisture content of boiled long‐life spaghetti was almost homogeneous. Texture of cooked spaghetti samples was evaluated using the force‐distance curve of a mechanical property test. For dried and frozen spaghetti, higher force was observed at the region corresponding to the low moisture core compared with the other types. The luncheon spaghetti and long‐life spaghetti showed a lower breaking force and a larger dip after the peak force representing soft and brittle texture caused by moisture homogeneity. These results indicated that MRI could be used for the quality evaluation of cooked spaghetti through imaging of the moisture distribution, which reflects the mechanical property.  相似文献   
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